A High Density Interconnector. HDI PCB is defined as a PCB with a higher wiring density per unit area than standard PCB. They have finer lines and spaces, smaller vias and capture pads and higher connection pad density than employed in conventional PCB technology.

HDI PCB is used to reduce size and weight, as well as to enhance electrical performance of the device. Also it is made through microvia and buried vias and sequential lamination with insulation materials and conductor wiring for higher density of routing.